1. Field of Invention
The present invention relates to a clutch actuator and, more particularly, to a clutch actuator for a vehicle capable of reducing the size and the weight of the clutch actuator by employing a simple-structure mechanism for actuating a diaphragm spring applied with the principle of the inclined plane.
2. Description of Related Art
In recent times, vehicle developing companies have been meeting with cutthroat competition for developing various means for improving fuel efficiency, such as hybrid vehicles, electric vehicles, manual transmission automation and the like. Particularly, there has been competitively developed an automated manual transmission which is more cost-competitive than the hybrid or electric vehicles, and whose shift feeling and price are substantially the same as those of a hydraulic automatic transmission and fuel efficiency is improved by 6 to 8 percent.
The automated manual transmission employs a manual shift mechanism of the conventional manual transmission, but is different from the manual shift mechanism of the conventional manual transmission in the actuation of a clutch and gear shift is automatically controlled by an actuator instead of being manually controlled.
FIG. 1 shows the structure of a clutch actuator for performing a shift mechanism of an automated manual transmission. A motor 1 for generating a driving power of the actuator is connected to a pushrod 3 through a reducer 2, and the seesaw movement of a release fork 4 is produced by the linear movement of the pushrod 3 to thereby actuate a release bearing 5.
However, an operating weight for actuating the release bearing quickly increases as an operating stroke becomes larger. Accordingly, the load of motor is required to increase in order to actuate the release bearing against the operating weight. Thus, when the clutch is actuated, a large current is consumed by the motor, thereby deteriorating the improving effect of vehicle fuel efficiency.
Further, since the structure and operating mechanism for actuating the release bearing are complicated, the size of the actuator increases, and thus the cost also increases. As the clutch actuator is separately installed outside the clutch housing, the clutch actuator is weak in noise and vibration when it is operated.
In the meantime, an actuator of a double clutch transmission (DCT) for a car was introduced in Korean Patent Application Publication No. KR 10-2008-0020232 A.
However, the actuator of this conventional technique also consumes a large current when the clutch is actuated. Accordingly, it is difficult to solve the problem that the improving effect of vehicle fuel efficiency is deteriorated.
Matters described as the background art are just to improve the background of the present invention, but it should not be understood that the matters correspond to the related art which has been already known to those skilled in the art.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.